• We reviewed the course of all 36 new patients with complete atrioventricular canal defect (CAVC) seen in a regional center from 1977 through 1982. Of this group of 36 patients, 28 had Down's syndrome. The eight children without Down's syndrome were all referred before 1 year of age. Surgical intervention was possible for each child. Of the 28 with Down's syndrome, 18 were referred before 1 year of age. Surgery intervention was possible in 17(94%) of 18. Of the ten children with Down's syndrome referred after 1 year of age, surgical therapy was not possible in five because of pulmonary vascular obstructive disease (PVOD). Since CAVC is known to progress to PVOD at an early age, it is not surprising that half of those patients referred after 1 year of age had become inoperable because of this complication. We therefore concluded that in spite of the severity of CAVC some children with Down's syndrome and this heart condition are being denied standard cardiac care by the process of late referral.